CE QUAL W2 Model Applications to Examine the Effects of Operations on Fish Habitat in Lake Murray

Transcription

1 CE QUAL W2 Model Applications to Examine the Effects of Operations on Fish Habitat in Lake Murray Meeting to Report on Preliminary Results Andy Sawyer and Jim Ruane, REMI May 22, 2007

2 Relicensing Issues Identified by the Water Quality Technical Working Committee The causes of striped bass fish kills reported in previous years, especially factors related to Saluda Hydro operations The effects of Unit 5 operations on entrainment of blue back herring Determination of operational changes that might increase habitat for striped bass and blue back herring Track any impacts that could occur to the tailwater cold water fishery due to potential operational changes

3 Factors Considered in Addressing Relicensing Issues Annual flow regimes Pool level management Unit 5 operations In lake and release water quality Habitat for striped bass and blue back herring Water quality, meteorological, and operations data over the period Emphasis will be placed on section of reservoir from Blacks Bridge to Saluda Dam

4 Plan for Using CE QUAL W2 to Address the Water Quality TWC Relicensing Issues 1. Analyze water quality, meteorological, flow, and operations data for the period of study 2. Set up CE QUAL W2 for the years when major striped bass fish kills occurred as well as other years 3. Run models to identify the causes that apparently contributed to the fish kills 4. Use the models to explore ways to avoid such fish kills in the future, with emphasis on project operations

5 Preliminary Findings High flow, especially during March August, is the primary cause for fish kills Higher flows cause the bottom of the lake to warm which in turn increases the rate of DO depletion Meteorological conditions can affect striper habitat Model results indicate that the temperature and DO range of tolerable striper habitat in Lake Murray is approximately: T< 27 o C and DO> 2.5 mg/l Preferential use of Unit 5 helps preserve colder bottom water and was predicted to improve DO and increase striper habitat

6 Lake Murray Surface Elevation Years with documented striped bass kills are red

7 Lake Murray Surface Elevation Typical Years Only (no special drawdowns) Years with documented striped bass kills are red

8 Average Annual Flow Saluda River at Chappells

9 Excel Table with Monthly Average Flow Below Saluda

10 Flow Frequency Saluda River Below Lake Murray Flow Frequency Based on Daily Average Flow in Saluda Tailrace, March June Only Daily Average Flow (cfs) % Exceedence

11 Cumulative Outflow March December Years with documented striped bass kills are red

12 Forebay Temperature Profiles

13 Forebay Temperature Profiles

14 Forebay Temperature Profiles

15 Forebay Temperature Profiles

16 Forebay DO Profiles

17 Forebay DO Profiles

18 Forebay DO Profiles

19 Forebay DO Profiles

20 Lake Murray Contour Plots June 2002 Temperature June 2005 Temperature June 2002 DO June 2005 DO

21 Lake Murray Contour Plots July 2002 Temperature July 2005 Temperature July 2002 DO July 2005 DO

22 Lake Murray Contour Plots August 2002 Temperature August 2005 Temperature August 2002 DO August 2005 DO

23 Lake Murray Contour Plots September 2002 Temperature September 2005 Temperature September 2002 DO September 2005 DO

24 Model Calibration Model was originally calibrated to 3 years: 1992, 1996 and 1997 Model SOD was adjusted in each of the 3 years to improve DO calibration

25 1996 Lake Murray Temperature Profiles Forebay Model vs. Data

26 1996 Lake Murray Temperature Profiles 19 Kilometers Upstream of Dam Model vs. Data

27 1996 Lake Murray DO Profiles Forebay Model vs. Data

28 1996 Lake Murray DO Profiles 19 Kilometers Upstream of Dam Model vs. Data

29 Release Temperature Model vs. Data 1996 Model Prediction vs Observed Discharge Temperature Model Hourly Observed Temperature C o /1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/ Date

30 Release DO Model vs. Data Dissolved Oxygen (mg/l) Model Prediction and Observed Discharge DO 0 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/ Date Model Hourly Observed

31 Temperature in Front of Unit 5 Model vs. Data 1996 Model Prediction vs Observed Temperature in front of Unit 5 25 Temperature C o Model Observed with Profile /1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/ Date

32 DO in Front of Unit 5 Model vs. Data 1996 Model Prediction vs Observed Temperature in front of Unit 5 Temperature C o Model Observed with Profile 0 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/ Date

33 Striped Bass Habitat in Lake Murray Zone Volume, T<27 and DO> Volume Mm /1 6/1 7/2 8/2 9/2 10/3 11/3

34 DO Animation with Striped Bass Habitat Highlighted

35 Sensitivity to Operations Original outflow assumption for all modeled years: Units 1, 2 and 4 Q < 9,600 cfs Unit 5 9,600 < Q < 15,600 cfs Unit 3 Q > 15,600 cfs When Unit 5 is operated first (Q < 6,000 cfs), cooler bottom water is conserved and availability of striper habitat improves

36 Evaluation of Raised Pool Levels Scenarios Considered: 354(Jan1) to 358(May1 Sept1) to 354(Dec 31) 350(Jan1) to 358(May1 Sept1) to 350(Dec 31) Assumptions: Assumed 500 cfs for minimum release Assumed reserve generation averaged 3hr every two weeks at 18,000 cfs Balance of releases were assumed to be used to supplement system demand Approach: The above scenarios were developed by KA using daily average flows using HEC ResSim CE QUAL W2 was run using daily average flows and release flows were adjusted so that target pool levels were attained Using the daily average flows that were adjusted using the CE QUAL W2 model the hourly flows for each day were developed using the assumptions above

37 Comparison of Original Flow Assumption and Alternative Unit 5 Operation Scenarios Volume Mm Zone Volume, T<27 and DO> Original Q Assumption 1600 Orig Q Assumption Unit 5 on first 1400 Orig Q Assumption Unit 5 on last /1 6/1 7/2 8/2 9/2 10/3 11/3 Volume Mm Zone Volume, T<27 and DO> Original Q Assumption 1600 Orig Q Assumption Unit 5 on first /1 6/1 7/2 8/2 9/2 10/3 11/3 Volume Mm Zone Volume, T<27 and DO> Original Q Assumption 1600 Orig Q Assumption Unit 5 on first 1400 Orig Q Assumption Unit 5 on last /1 6/1 7/2 8/2 9/2 10/3 11/3 Volume Mm Zone Volume, T<27 and DO> Original Q Assumption 1400 Orig Q Assumption Unit 5 on first /1 6/1 7/2 8/2 9/2 10/3 11/3

38 1998 Animation Comparison of Original Flow Assumption and Unit 5 on First Scenario

39 Tailrace Temperature Comparison of Original Flow Assumption and Unit 5 on First Scenario Temperature o C Release Temperature Current Unit 5 on First 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Temperature o C Current Unit 5 on First 1996 Release Temperature 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Temperature o C Release Temperature Current Unit 5 on First 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13 Temperature o C Release Temperature Current Unit 5 on First 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13

40 Tailrace DO Comparison of Original Flow Assumption and Unit 5 on First Scenario Dissolved Oxygen (mg/l) 1991 Release DO Current 4 Unit 5 on First /1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Dissolved Oxygen (mg/l) 1996 Release DO Current 4 3 Unit 5 on First /1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Dissolved Oxygen (mg/l) 1998 Release DO Current 3 2 Unit 5 on First 1 0 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13 Dissolved Oxygen (mg/l) 2005 Release DO Current 3 2 Unit 5 on First 1 0 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13

41 Forebay Temperature Profiles Comparison of Original Flow Assumption and Unit 5 on First Scenario

42 Temperature at the Intake to Unit 5 Comparison of Original Flow Assumption and Unit 5 on First Scenario Temperature o C Temperature in front of Unit 5 Current Unit 5 on First 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Temperature o C Current 1996 Temperature in front of Unit 5 Unit 5 on First 1/1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Temperature o C Temperature in front of Unit 5 Current Unit 5 on First 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2 Temperature o C Temperature in front of Unit 5 Current Unit 5 on First 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27

43 DO at the Intake to Unit 5 Comparison of Original Flow Assumption and Unit 5 on First Scenario Dissolved Oxygen (mg/l) 1991 DO in front of Unit Current 3 Unit 5 on First /1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Dissolved Oxygen (mg/l) 1996 DO in front of Unit Current 4 3 Unit 5 on First /1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Dissolved Oxygen (mg/l) 1998 DO in front of Unit Current 2 Unit 5 on First 1 0 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2 Dissolved Oxygen (mg/l) 2005 DO in front of Unit Current 2 Unit 5 on First 1 0 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27

44 1991 Pool Level Management Elevation (ft) 1991 Surface Elevation Actual 352 Elevation 354 Scenario Elevation 350 Scenario /1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 1991 Zone Volume, T<27 and DO>2.5 Volume Mm Original Q Assumption 1600 Elev 354 Scenario 1400 Elev 350 Scenario /1 6/1 7/2 8/2 9/2 10/3 11/3

45 1996 Pool Level Management Elevation (ft) 1996 Surface Elevation Actual 352 Elevation 354 Scenario /1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 1996 Zone Volume, T<27 and DO> Original Q Assumption Volume Mm Elev 354 Scenario /1 6/1 7/2 8/2 9/2 10/3 11/3

46 1998 Pool Level Management Elevation (ft) 1998 Surface Elevation Actual Elevation 354 Scenario 351 Elevation 350 Scenario /1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 1998 Zone Volume, T<27 and DO>2.5 Volume Mm Original Q Assumption 1600 Elev 354 Scenario 1400 Elev 350 Scenario /1 6/1 7/2 8/2 9/2 10/3 11/3

47 2005 Pool Level Management Elevation (ft) 2005 Surface Elevation Actual 352 Elevation 354 Scenario 351 Elevation 350 Scenario /1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 2005 Zone Volume, T<27 and DO> Original Q Assumption Elev 354 Scenario Volume Mm Elev 350 Scenario /1 6/1 7/2 8/2 9/2 10/3 11/3

48 Excel Plots

49 Temperature and DO at the Intake to Unit 5 with Pool Level Management Temperature o C Current 1996 Temperature in front of Unit 5 Elevation 354 Scenario 1/1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Temperature o C Temperature in front of Unit 5 Current Elevation 354 Scenario 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2 Dissolved Oxygen (mg/l) 1996 DO in front of Unit Current 4 3 Elevation 354 Scenario /1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Dissolved Oxygen (mg/l) 1998 DO in front of Unit Current 3 2 Elevation 354 Scenario 1 0 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2

50 Comparison of Current Phosphorus Load and Reduced Phosphorus Scenario 1998 Zone Volume, T<27 and DO>2.5 Volume Mm Current Phosphorus Load Reduced TP and SOD /1 6/1 7/2 8/2 9/2 10/3 11/ Zone Volume, T<27 and DO>2.5 Volume Mm Current Phosphorus Load 1600 Reduced TP and SOD /1 6/1 7/2 8/2 9/2 10/3 11/3

51 Preliminary Conclusions Nutrients are the single dominant factor that can enhance striped bass habitat Flow is a dominant factor, but cannot be controlled to avoid fish kills Met conditions can be a periodic factor that alleviates otherwise dominant factors like flow Striped bass habitat conditions can be improved in some years by maintaining high summer pool levels (~ elev. 358 ft) Unit 5 preferential operations can improve striped bass habitat in some years

52 Next Steps 1. For selected years, finalize assessment (i.e., assess changes in releases) of operating guide for U5 preference for first on, last off operation using the hourly releases 2. For selected years, finalize assessment of maintaining summer pool levels at For selected years, finalize assessment of the combination of maintaining summer pool levels at 358 with U5 preference for first on, last off operation using the hourly releases 4. Analyze additional years, especially a low flow year 5. Assess effects of minimum winter pool level, including effects on Little Saluda embayment, increased SOD, internal nutrient cycling, aquatic plants, sedimentation in coves,